Couplings for the joining of a pump shaft to an air motor or hydraulic motor output shaft are well known in the art. Such couplings typically consist of a knob on the end of the pump shaft having an underside shoulder which extends radially outwardly at right angles to the axis of the shaft. This shoulder is gripped by a two piece annular collar which is in turn drawn upwardly by a nut which screws to the motor shaft. Since constructions have typically been less than optimal as the substantial alternating loads imposed by the motor shaft can lead to failure of the coupling in extreme circumstances.
It is therefore an object of this invention to provide a coupling design which provides enhanced ability to handle increased loads while at the same time remains easy to assemble and disassemble as well as to manufacture.